Recently, technology for writing tracks of a magnetic disk at high density has been developed. One of types of the technology is, for example, shingled write recording that partially overlaps the tracks. Since the data can be written on the tracks at high density by the shingled write recording, a recording capacity can be increased.
When the shingled write recording is applied, for example, if a positioning error of a first track occurs in a second track direction and a positioning error of the second track occurs in the first track direction, in an adjacent recording region of the first track and the second track written over a part of the first track, a width of the first track is narrowed. If a narrowing amount increase, the data written on the first track may be overwritten or deleted by the data of the second track at the narrowed portion.
Incidentally, technology of preventing the overwriting by setting a width of a subsequent track to be recorded to be an appropriate certain width based on the positioning error of the written track has been developed. However, a large amount of memory is required to store positioning errors of plural written tracks recorded at various radial positions on the magnetic disk.
For this reason, processing of defining a limit value for the positioning error and interrupting writing data if the positioning error exceeds the limit value may be executed to prevent the recorded data from being damaged. In this case, if the limit value is smaller than needed appropriate value, probabilities for the positioning error to reach the limit value are increased, the number of times of interrupting the writing is increased and, consequently, the recording performance may be lowered.